1. Field of the Invention
The present invention pertains, in general, to flooring materials using phenol composite resin, and more specifically, to a floor-covering material suitable for use in under-floor heating systems or floors, which has the advantages of little heat-distortion and no curling, with excellent surface hardness.
2. Description of the Prior Art
Typically, a floor sheet material for use in the Korean under-floor heating system, which is registered to Korean Pat. No. 189372, comprises a core layer, a shaping layer and a transparent protective layer successively laminated on a surface of waterproof plywood, and a balance layer attached to the opposite side of the plywood. The core layer is a sheet obtained by incorporating a sheet of paper with phenol resin, and the shaping layer and the surface layer are sheets of paper-incorporated melamine resin. On the bottom side of the waterproof plywood, the balance layer consisting of a sheet of paper-incorporated melamine resin is necessarily laminated to alleviate heat-distortion or curling of the surface layer.
Such conventional flooring materials suffer from the disadvantage of a readily-scratched surface due to low surface hardness. In addition, even though the balance layer is laminated onto the bottom side of the flooring material, distortion or curling of the flooring material cannot be prevented, attributable to the surface layer, which largely expands or contracts by heat.
Therefore, it is an object of the present invention to alleviate the problems in the prior art and to provide a floor-covering material which is advantageous in light of high surface strength, low heat-distortion, prevention of curling, and unnecessary balance layer on a bottom side of the flooring material, by preparing a prepreg with the use of phenol composite resin, instead of typical phenol resin or melamine resin, and forming a surface layer of the floor-covering material therefrom.